Processed foods contribute to weight gain for several key reasons. They’re often softer and easier to chew and swallow, leading to faster and sometimes mindless eating. This can result in consuming more food before your body realizes it's full. They generally contain less fiber compared to whole foods. Fiber is crucial for satiety; without it, you're likely to feel hungry sooner, prompting overeating. And processed foods are typically calorie-dense but nutrient-poor. They provide a high amount of calories without the essential nutrients your body needs, leading to unfulfilled nutritional requirements and potential overconsumption of food to meet these needs.